1. Field of the Invention
The present invention generally relates to equipment used in a telecommunications system, and more particularly relates to devices and components used in telephone systems. Even more specifically, the invention relates to switching modular jacks used in telephone systems for testing the telephone lines, among other uses.
2. Description of the Prior Art
U.S. Pat. No. 5,704,797 (Meyerhoefer, et al.) discloses a switchable electrical socket used for testing telephone lines. The electrical socket described in the Meyerhoefer, et al. patent is, essentially, an RJ11 modular jack having switching capabilities. Generally, the modular jack acts as a switch to disconnect electrically the tip (green) and ring (red) lines coming into a network interface device (NID) from a telephone company (“telco”) from the subscriber telephone wiring downstream of the NID in order to test the lines to determine where a fault may lie.
Since telephone subscribers are permitted to install their own telephone equipment and other communications equipment, such as modems, routers, switches, residential gateways and the like, these subscribers are responsible for the care and maintenance of such equipment and the wiring in the subscriber premises. The telephone company is responsible for service only up to the juncture between the telco wiring and the subscriber wiring, that is, generally at the NID. Therefore, it is important to provide a device which allows a subscriber to disconnect and reconnect the subscriber wiring from the telco wiring to isolate where a wiring fault occurs, i.e., either in the telco wiring upstream of the NID or the wiring in the customer (subscriber) premises.
The switchable RJ11 modular jack disclosed in the aforementioned Meyerhoefer, et al. patent fulfills this requirement. Such a switchable modular jack may be incorporated directly in a customer bridge module in the NID, or may be situated outside the NID in a separate housing and electrically connected to the components in the NID.
With high speed data now being provided to customer premises by the telephone company over cables having multiple twisted pairs of wires, not only is the twisted pair of tip (green) and ring (red) lines of POTS (Plain Old Telephone Service) wiring used, but also the commonly recognized black and yellow twisted pair of lines is used. To accommodate and interconnect with such double twisted pairs of wires, RJ14 modular jacks and plugs are commonly used rather than RJ11 jacks and plugs. Since the black and yellow wires also carry telecommunications signals, just like the tip (green) and ring (red) wires, there is a need to test these lines, as well.